[RFC PATCH net-next v5 22/25] net: dsa: qca8k: improve internal mdio read/write bus access

From: Ansuel Smith
Date: Mon May 10 2021 - 22:10:00 EST


Improve the internal mdio read/write bus access by caching the value
without accessing it for every read/write.

Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
---
drivers/net/dsa/qca8k.c | 28 +++++++++++++++-------------
1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index 307fe7eb03f3..920cdb1ff2b9 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c
@@ -655,6 +655,7 @@ static int
qca8k_mdio_write(struct mii_bus *salve_bus, int phy, int regnum, u16 data)
{
struct qca8k_priv *priv = salve_bus->priv;
+ struct mii_bus *bus = priv->bus;
u16 r1, r2, page;
u32 val;
int ret;
@@ -669,22 +670,22 @@ qca8k_mdio_write(struct mii_bus *salve_bus, int phy, int regnum, u16 data)

qca8k_split_addr(QCA8K_MDIO_MASTER_CTRL, &r1, &r2, &page);

- mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED);
+ mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);

- ret = qca8k_set_page(priv->bus, page);
+ ret = qca8k_set_page(bus, page);
if (ret)
goto exit;

- qca8k_mii_write32(priv->bus, 0x10 | r2, r1, val);
+ qca8k_mii_write32(bus, 0x10 | r2, r1, val);

- ret = qca8k_mdio_busy_wait(priv->bus, QCA8K_MDIO_MASTER_CTRL,
+ ret = qca8k_mdio_busy_wait(bus, QCA8K_MDIO_MASTER_CTRL,
QCA8K_MDIO_MASTER_BUSY);

exit:
/* even if the busy_wait timeouts try to clear the MASTER_EN */
- qca8k_mii_write32(priv->bus, 0x10 | r2, r1, 0);
+ qca8k_mii_write32(bus, 0x10 | r2, r1, 0);

- mutex_unlock(&priv->bus->mdio_lock);
+ mutex_unlock(&bus->mdio_lock);

return ret;
}
@@ -693,6 +694,7 @@ static int
qca8k_mdio_read(struct mii_bus *salve_bus, int phy, int regnum)
{
struct qca8k_priv *priv = salve_bus->priv;
+ struct mii_bus *bus = priv->bus;
u16 r1, r2, page;
u32 val;
int ret;
@@ -706,26 +708,26 @@ qca8k_mdio_read(struct mii_bus *salve_bus, int phy, int regnum)

qca8k_split_addr(QCA8K_MDIO_MASTER_CTRL, &r1, &r2, &page);

- mutex_lock_nested(&priv->bus->mdio_lock, MDIO_MUTEX_NESTED);
+ mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);

- ret = qca8k_set_page(priv->bus, page);
+ ret = qca8k_set_page(bus, page);
if (ret)
goto exit;

- qca8k_mii_write32(priv->bus, 0x10 | r2, r1, val);
+ qca8k_mii_write32(bus, 0x10 | r2, r1, val);

- ret = qca8k_mdio_busy_wait(priv->bus, QCA8K_MDIO_MASTER_CTRL,
+ ret = qca8k_mdio_busy_wait(bus, QCA8K_MDIO_MASTER_CTRL,
QCA8K_MDIO_MASTER_BUSY);
if (ret)
goto exit;

- val = qca8k_mii_read32(priv->bus, 0x10 | r2, r1);
+ val = qca8k_mii_read32(bus, 0x10 | r2, r1);

exit:
/* even if the busy_wait timeouts try to clear the MASTER_EN */
- qca8k_mii_write32(priv->bus, 0x10 | r2, r1, 0);
+ qca8k_mii_write32(bus, 0x10 | r2, r1, 0);

- mutex_unlock(&priv->bus->mdio_lock);
+ mutex_unlock(&bus->mdio_lock);

if (val >= 0)
val &= QCA8K_MDIO_MASTER_DATA_MASK;
--
2.30.2